Document feeders on copiers, microfilmers, fax machines, printers and other business equipment rely on guides prior to feeding to align the documents. On some equipment, the guides move independently of one another and on other equipment, they are coupled with a rack and pinion arrangement which allows them to move together about the center line of the pinion gear.
U.S. Pat. No. 3,406,964 is directed to a pack holder for supporting a stack of sheet material to be fed therefrom. The pack holder is adjustable through equidistant sliding of parallel guide members. The guide members are mounted on pairs of gear racks. Pinion gears operatively associated with the gear racks rotate to slide the gear rack and the guide members. Rotation of the pinion gears is effected through a gear portion rotatably secured to the pack holder intermediate the pinion gears. A handle on the gear portion is used to rotate the gear portion and consequently adjust the guide members.
This provides improved paper trays by adapting the side guides for self-centering movement so that sheet material of various sizes may be accommodated in the pack holder which, in turn, can be positioned with a sheet forwarding mechanism.
Accordingly, the pack holder includes a platform with a pair of side guides supported thereon, each side guide having a pair of gear racks secured thereto and each meshing with a pinion gear secured for rotation to the base of the pack holder. Movement of the side guides is effected by means of a gear sector rotatably secured to the base of the pack holder and cooperating with the pinions. A handle is provided and secured to the section for manually rotating the gear sector and thereby causing rapid equidistant self-centering movement of the side guides.
U.S. Pat. No. 5,148,228 discloses a pair of sheet edge holders that are adjustably connected to each other using a gear unit. The apparatus is provided with a pair of edge holders opposedly arranged about the feed path for holding edge portions of the recording medium.
When feeding documents into a microfilm camera to obtain the maximum quality image on film, the document needs to be fed on the center of the transport system. This is where the feed and separating rollers are located in the feeder. In addition, when a document is fed on center, it is assured that it will travel under the optimum profile of the illumination system with the least amount of skew.